Something like this (copy and paste the step below into VBP):
<step action='SourceSafe' type='0'>
<AutoLocate type='11'>-1</AutoLocate>
<CompareOpt type='3'>2</CompareOpt>
<Database>%SAMPLEDB%</Database>
<LongFilenames type='11'>-1</LongFilenames>
<Operation>Pin</Operation>
<Project>$/Source/MyNETProjects.sln</Project>
<PromptOff type='11'>-1</PromptOff>
<Recurse type='11'>-1</Recurse>
<ShowCmd type='11'>-1</ShowCmd>
<ShowFilesOnly type='11'>0</ShowFilesOnly>
<TimeOpt type='3'>1</TimeOpt>
<Username>%SSUSER%</Username>
<Version>1</Version>
<WriteOpt type='3'>0</WriteOpt>
<description>Pin version 1 of MyNETProjects.sln</description>
<indent type='3'>1</indent>
<name>pin</name>
<outputfrom type='3'>1</outputfrom>
</step>
See
http://msdn.microsoft.com/library/de...sgrfss_pin.asp for more details.