How to improve GTK aspect in Ekiga ?

[YannUbuntu <yannubuntu gmail com>]

Dear all,

I am new here. I hope you can help with the following issue :
Ekiga (SIP client for linux and windows) is coded in GTK 2.16 , but
its main interface (tabs, lists...) does not look nice in Windows.
Are there ways to get "round" tabs ? or nice "skin" with GTK ?

Please see screenshot and dev comments on :
https://bugzilla.gnome.org/show_bug.cgi?id=619812

Best regards
~Yann