In the Pidgin profile directory called .pidgin (the location varies by operating system), there is a subdirectory called smileys. In there is a subdirectory for all the smiley themes that are currently installed.
To create a new theme, make a new directory inside the smileys directory. Then put all the smiley image files (PNG or GIF format) inside. Finally, create a text file called theme. This is where you’ll define all the smileys.
The format of the theme file is similar to the old Windows .ini file (remember those?). There are multiple sections separated by a section heading in square brackets as shown below.
smile.gif :) :-) (: (-:
sad.gif :( :-( )-: ):
bigsmile.gif :D :-D
yahoo_angel.gif o:-) O:-) 0:-)
yahoo_angry.gif X-( x-( X( x(
yahoo_bigsmile.gif :D :-D :d :-d
The section heading indicates for which instant messaging network the smilies apply (default applies to any network that isn’t already defined). Then, each line below the heading is the name of the smiley image file followed by one or more examples of the smiley text that Pidgin will look for to do the substitution. You can even add your own if people you chat with use a different combination of characters to represent a particular smiley.
Note that if you install a smiley theme and you don’t get any smiley images for some protocols, check the theme file to see if it has a section for that protocol. Chances are that it doesn’t. So, you can either create a section for it, or add a section called default that contains the smilies that you want to appear for any unspecified protocol. Be sure to put the default section above any others.