Wow, dang that would have been cool.
I understand not wanting to write code to bridge to another app you haven't previously supported....but i also understand it's hard to bridge frameworks if you don't speak the language and understand the variables or if you don't have any type of a reference to do so.
I guess that's a one up for panels like lxadmin
However, the developers of ISPConfig were kind enough to release a great panel under open source.
Even though I like their product, WHMCS developers decided to release it closed source like the homosexuals they are. Pussies!