You can use Sparkle to generate a Mail signature:
Make the desired signature in Sparkle
Don’t overlap Photo & Text
Publish to disk
Open index.html in Safari
Copy this content in Safari
Paste this in Mail signature
Drag this signature into mail account
Select the desired standard signature
Close Mail preferences
You may need some tweaking, but it works!
Okay, but does it work also to PC mail and stuff…
if so this is a nice tweak!!!
I thought this was a Mac platform only…
That is, but if you send a mail to somebody with a PC (plenty of them around ;-)), what do they see?
No idea yet. Good point
Well the code Sparkle generates for websites is designed to be compatible with Windows browsers (including some versions of the beloved Internet Explorer), and Android phones.
But that’s a cool hack 
Do I understand this right: you mean ‘copy from the Safari’ window?
Sorry, yes, copy from Safari