In regards to adding a picture or signature in Horde you can do so by:
1 ) Log into Web Mail on the left side of http://www.doteasy.com/
with *email address* and the *password*.
2 ) Click on Continue Sign in
3 ) Click on Read Mail using Horde (if Auto Load Message does not appear)
4 ) Click Log In
5 ) Click on Options at the Top
6 ) On the top right where it says Edit Options for: and shows a drop down box, select Mail from the list and click on it
7 ) Click on Personal Information
8 ) Here you Can Enter a Signature into the box listed.
You can also load an image into here too by adding the HTML Code for it, EX:
<img src="*location of image on your server*" />
9 )Click Save Options.
All mail sent through Horde for this email address will now have a signature on it. Note that unless a person is reading this message in HTML format as you are sending in, this will not show up.