softphone for windows CE 6

Anand Computer Systems
Hi,

My name is Sameer Naik from India / Maharastra / Pune
From company Anand Computer Systems.
We have approx. 2500 WYSE Thin clients with Windows CE 6 installed on it.
We want a soft phone for this device. it must work on windows ce 6.
Have any body any idea about any comparable soft phone which will work on
windows CE. Waiting for reply, thanks in advance.

Thanks,
Sameer Naik
Anand Computer Systems
Swamipuram Building, Shop No C-7, 8 & 9,
2160 B  Sadashiv Peth , Near Dandekar Bridge,
Near Lokmanya Nagar, Sane Guruji Road, Pune – 411030