No virii found but hacker still gets in

I'm posting on behalf of my friend.
He runs a forum and a hacker seems to be able to get into his Forum account time and again, the forum software is fully updated and there are no working public exploits for it, and the passwords are encrypted with md5 and he tried using a really long and complicated password and the hacker still managed to get in, so I think that rules out the server being backdoored because downloading the database with the MD5 hashes would take years to crack, so it must be on his pc.

A KAV/TDS scan doesn't find anything.
Here's the Hijack this log:
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\LEXBCES.EXE
C:\WINDOWS\Explorer.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\system32\LEXPPS.EXE
C:\PROGRA~1\Zone Labs\ZoneAlarm\zapro.exe
C:\WINDOWS\system32\rundll32.exe
C:\WINDOWS\system32\RUNDLL32.EXE
C:\Program Files\Common Files\Real\Update_OB\realsched.exe
C:\Program Files\MUSICMATCH\MUSICMATCH Jukebox\mmtask.exe
C:\Program Files\MSN Messenger\MsnMsgr.Exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Messenger\msmsgs.exe
C:\Program Files\TerraTec\DMX 6fire\DMX6Fire.exe
C:\Program Files\MSI\PC Alert 4\PCAlert4.exe
C:\Program Files\Apache Group\Apache\Apache.exe
C:\Program Files\Executive Software\DiskeeperServer\DKService.exe
C:\Program Files\Apache Group\Apache\Apache.exe
C:\Program Files\Common Files\Microsoft Shared\VS7Debug\mdm.exe
C:\Program Files\MySQL\bin\mysqld-nt.exe
C:\WINDOWS\System32\nvsvc32.exe
C:\WINDOWS\system32\ZoneLabs\vsmon.exe
C:\Program Files\mIRC\mirc.exe
C:\Program Files\Trillian\trillian.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\HTTP-Tunnel\HTTP-TunnelClient.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Hijack This\HijackThis1982.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://minisearch.startnow.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.startnow.com/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Bar = http://minisearch.startnow.com
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://red.clientapps.yahoo.com/customize/ie/defaults/stp/ymsgr*http://my.yahoo.com
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,SearchAssistant = http://minisearch.startnow.com
R1 - HKCU\Software\Microsoft\Internet Explorer\Search,CustomizeSearch = http://minisearch.startnow.com
R1 - HKLM\Software\Microsoft\Internet Explorer\Search,Default_Search_URL = http://minisearch.startnow.com
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = http://red.clientapps.yahoo.com/customize/ie/defaults/su/ymsgr/*http://www.yahoo.com
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyServer = 68.15.135.37:80
N3 - Netscape 7: user_pref("browser.search.defaultengine", "engine://C%3A%5CProgram%20Files%5CNetscape%5CNetscape%5Csearchplugins%5CSBWeb_01.src"); (C:\Documents and Settings\User\Application Data\Mozilla\Profiles\default\j7x00fgh.slt\prefs.js)
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 6.0\Reader\ActiveX\AcroIEHelper.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [Zone Labs Client] C:\PROGRA~1\Zone Labs\ZoneAlarm\zapro.exe
O4 - HKLM\..\Run: [NeroFilterCheck] C:\WINDOWS\system32\NeroCheck.exe
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\System32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] nwiz.exe /install
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\System32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Common Files\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [KAVPersonal50] C:\Program Files\Kaspersky Lab\Kaspersky Anti-Virus Personal\kav.exe /minimize
O4 - HKLM\..\Run: [mmtask] C:\Program Files\MUSICMATCH\MUSICMATCH Jukebox\mmtask.exe
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\MSN Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Yahoo! Pager] C:\Program Files\Yahoo!\Messenger\ypager.exe -quiet
O4 - HKCU\..\Run: [MSMSGS] "C:\Program Files\Messenger\msmsgs.exe" /background
O4 - Global Startup: Adobe Gamma Loader.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: DMX 6fire 2496 ControlPanel.lnk = ?
O4 - Global Startup: PC Alert 4.lnk = C:\Program Files\MSI\PC Alert 4\PCAlert4.exe
O8 - Extra context menu item: &Google Search - res://C:\Program Files\Google\GoogleToolbar2.dll/cmsearch.html
O8 - Extra context menu item: Backward &Links - res://C:\Program Files\Google\GoogleToolbar2.dll/cmbacklinks.html
O8 - Extra context menu item: Cac&hed Snapshot of Page - res://C:\Program Files\Google\GoogleToolbar2.dll/cmcache.html
O8 - Extra context menu item: Download All by FlashGet - C:\Program Files\FlashGet\jc_all.htm
O8 - Extra context menu item: Download using FlashGet - C:\Program Files\FlashGet\jc_link.htm
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O8 - Extra context menu item: Si&milar Pages - res://C:\Program Files\Google\GoogleToolbar2.dll/cmsimilar.html
O8 - Extra context menu item: Translate into English - res://C:\Program Files\Google\GoogleToolbar2.dll/cmtrans.html
O8 - Extra context menu item: Translate Page - res://C:\Program Files\Google\GoogleToolbar1.dll/cmtrans.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - (no file)
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - (no file)
O9 - Extra button: Real.com - {CD67F990-D8E9-11d2-98FE-00C0F0318AFE} - C:\WINDOWS\System32\Shdocvw.dll
O9 - Extra button: FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - C:\Program Files\FlashGet\flashget.exe
O9 - Extra 'Tools' menuitem: &FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - C:\Program Files\FlashGet\flashget.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O16 - DPF: {4E330863-6A11-11D0-BFD8-006097237877} (InstallFromTheWeb ActiveX Control) - http://tw.msi.com.tw/autobios/client/iftwclix.cab
O16 - DPF: {665585FD-2068-4C5E-A6D3-53AC3270ECD4} (FileSharingCtrl Class) - http://appdirectory.messenger.msn.com/AppDirectory/P4Apps/FileSharing/en/filesharingctrl.cab
O16 - DPF: {75D1F3B2-2A21-11D7-97B9-0010DC2A6243} (SecureLogin.SecureControl) - http://secure2.comned.com/signuptemplates/ActiveSecurity.cab
O16 - DPF: {8E0D4DE5-3180-4024-A327-4DFAD1796A8D} (MessengerStatsClient Class) - http://messenger.zone.msn.com/binary/MessengerStatsClient.cab28578.cab
O16 - DPF: {AD7FAFB0-16D6-40C3-AF27-585D6E6453FD} - http://dload.ipbill.com/del/loader.cab
O16 - DPF: {D1E7CBDA-E60E-4970-A01C-37301EF7BF98} (Measurement Service Client v.3.4) - http://ccon.madonion.com/global/msc34.cab

Please help

(Sorry if I forgot anything, I'm tired)