[imp] How to customize the signature (color, ...) ?

[Philippe Reymond]

Hi !

My company uses Horde and IMP as webmail.

I would
like to customize my
signature but it seems that we can only type plain text.

So, how to customize the
color,
size and font of the signature? 

For example, in my previous
company (we used OpenWebMail), it was possible to type HTML to change the look
of the signature ... 

Thank you for your help!
 Philippe