SQL Server 2005 Install Error (Error 29528. Unexpected Error While Installing Performance Counters. )

I'm currently receiving the following error message whilst attempting to install SQL Server 2005 Standard Edition on Windows Server 2003 (32 Bit):
Error 29528. The setup has encountered an unexpected error while Installing performance counters. The error is: The system cannot find the file specified.

This server already has an install of SQL Server 2000 as the default instance. I'm attempting to install a new named instance of SQL Server 2005.

Extract from log:

<Func Name='LaunchFunction'>
Function=Do_sqlPerfmon2
<Func Name='GetCAContext'>
<EndFunc Name='GetCAContext' Return='T' GetLastError='0'>
Doing Action: Do_sqlPerfmon2
PerfTime Start: Do_sqlPerfmon2 : Tue Jun 12 10:20:02 2007
<Func Name='Do_sqlPerfmon2'>
<EndFunc Name='Do_sqlPerfmon2' Return='0' GetLastError='2'>
PerfTime Stop: Do_sqlPerfmon2 : Tue Jun 12 10:20:02 2007
MSI (s) (4C:FC) [10:20:02:833]: Executing op: ActionStart(Name=Rollback_Do_sqlPerfmon2.D20239D7_E87C_40C9_9837_E70B8D4882C2,Description=Removing performance counters,)
<EndFunc Name='LaunchFunction' Return='0' GetLastError='0'>
MSI (s) (4C:FC) [10:20:02:849]: Executing op: CustomActionSchedule(Action=Rollback_Do_sqlPerfmon2.D20239D7_E87C_40C9_9837_E70B8D4882C2,ActionType=1281,Source=BinaryData,Target=Rollback_Do_sqlPerfmon2,CustomActionData=1
0
0
Removing performance counters
200000

DTSPipeline
C:Program FilesMicrosoft SQL Server90DTSBinnDTSPERF.INI
)
MSI (s) (4C:FC) [10:20:02:849]: Executing op: ActionStart(Name=Do_sqlPerfmon2.D20239D7_E87C_40C9_9837_E70B8D4882C2,Description=Installing performance counters,)
MSI (s) (4C:FC) [10:20:02:849]: Executing op: CustomActionSchedule(Action=Do_sqlPerfmon2.D20239D7_E87C_40C9_9837_E70B8D4882C2,ActionType=1025,Source=BinaryData,Target=Do_sqlPerfmon2,CustomActionData=1
0
0
Installing performance counters
200000

C:Program FilesMicrosoft SQL Server90DTSBinnDTSPERF.INI
C:Program FilesMicrosoft SQL Server90DTSBinnDTSPERF.H
C:Program FilesMicrosoft SQL Server90DTSBinnDTSPipelinePerf.dll
DTSPipeline
0
DTSPipeline

PrfData_Open
PrfData_Collect
PrfData_Close
)
MSI (s) (4C:94) [10:20:02:864]: Invoking remote custom action. DLL: C:WINDOWSInstallerMSI1683.tmp, Entrypoint: Do_sqlPerfmon2
<Func Name='LaunchFunction'>
Function=Do_sqlPerfmon2
<Func Name='GetCAContext'>
<EndFunc Name='GetCAContext' Return='T' GetLastError='0'>
Doing Action: Do_sqlPerfmon2
PerfTime Start: Do_sqlPerfmon2 : Tue Jun 12 10:20:02 2007
<Func Name='Do_sqlPerfmon2'>
<EndFunc Name='Do_sqlPerfmon2' Return='2' GetLastError='2'>
PerfTime Stop: Do_sqlPerfmon2 : Tue Jun 12 10:20:02 2007
Gathering darwin properties for failure handling.
Error Code: 2
MSI (s) (4C!F0) [10:23:46:381]: Product: Microsoft SQL Server 2005 Integration Services -- Error 29528. The setup has encountered an unexpected error while Installing performance counters. The error is: The system cannot find the file specified.Error 29528. The setup has encountered an unexpected error while Installing performance counters. The error is: The system cannot find the file specified.

You can ignore this and it will complete the installation, but subsequently trying to patch with SP2 will fail on the same sections - Hotfix.exe crashes whilst attempting to patch Database Services, Integration Services and Client Components (3 separate crashes).

I've removed SQL Server 2005 elements and tried to re-install, but it's not improved the situation.

Any ideas?