Hey,
You can perform that task within an InfoPath form itself. The form will need to be fully trusted.
VB Script Code snippet below:
'Purpose to clear the form cache on the client machine
'date 04/22/2006
'misc ''C:\Program Files\Microsoft Office\OFFICE11\INFOPATH.EXE'' /cache clearall
Dim wshShell
Dim sRun, sParam, sMsg
sParam = ...