hey,
is it possible to set follow me option only for external incoming calls?
no ideas or not possible? 
come on, nobody got the same problem? 
Assuming you’re using FreePBX, its not possible out of the box (at least not that i know of). You could however write a dialplan hack that goes through a check (using the custom_destination etc function) that checks if internal, don’t do follow me (i.e. do a direct dial ) else case, dial as usual using goto for instance…