Here is the step...
<step action='SourceSafe' type='0'>
<AutoLocate type='11'>-1</AutoLocate>
<CompareOpt type='3'>2</CompareOpt>
<Database>\\VSS_REPOSITORY</Database>
<LocalPath>%PROJDIR%</LocalPath>
<LongFilenames type='11'>0</LongFilenames>
<NoGet type='11'>-1</NoGet>
<Operation>History</Operation>
<Project>$/VSS_PROJECT/*.*</Project>
<PromptOff type='11'>-1</PromptOff>
<Recurse type='11'>0</Recurse>
<ShowCmd type='11'>-1</ShowCmd>
<ShowFilesOnly type='11'>0</ShowFilesOnly>
<TimeOpt type='3'>1</TimeOpt>
<Username>BUILD</Username>
<Version>~L%Previous_Version%</Version>
<WriteOpt type='3'>0</WriteOpt>
<checked type='11'>0</checked>
<description>Display a history of changes to source files since a label</description>
<indent type='3'>1</indent>
<name>Get History of Project</name>
<script><![CDATA[Function vbld_StepDone()
If vbld_FSO.FileExists("c:\out.txt") Then
Builder.LogMessage vbld_GetFileContents("c:\out.txt")
End If
End Function]]></script>
</step>