uninstall problem and nsexec ?

Hi

I am calling the following function in the installer. But its not being called. Have tried ...

nsExec::ExecToLog '"$PLUGINSDIR\gacutil.exe" -u "trikatusupportlibrary"'

gacutil.exe is a util to add and remove files from the .NET assembly
at dos it should read

c:\gacutil -u trikatusupportlibrary

Thanks

Paul