EMWProf does not appear to migrate the created Outlook signatures.
Outlook signatures is not part of the Outlook profile. It is an Outlook setting that is stored in the Windows profile.
If the Source user's Windows profile has been updated for the Target user, the Outlook signatures should remain in Windows profile.
Outlook signatures can be located from :
Windows XP
C:\Documents and Settings\Username\Application Data\Microsoft\Signatures\
Vista and Windows 7
C:\Users\Username\AppData\Roaming\Microsoft\Signatures\