Travelsim, First Impressions

[Effendi]

I just received my Travelsim today... and it has some problems!

Here are my experiments:
- Italy landline: ok
- Italy mobile: no (Wind, 3)
- Germany landline: ok
- Germany mobile: no (O2)
- Czech mobile: no (Oskar, T-Mobile, Eurotel)
- Croatia mobile: no (T-Mobile)
- Austria mobile no (T-Mobile) (OnZoone help number :P)
- Lithuania mobile: ok (Bite)
- Latvia mobile: ok (Amigo)
- Estonia mobile: ok (Elisa, Tele2)
- Poland mobile: ok (Plus, Era)
- New Zeland mobile: ok (Vodafone)
- Russia mobile: ok (Tele2)

I cannot call any Italian, German, Austrian, Croatian or Czech mobile, while it works with both Italian and German landline. When I try to call a mobile I receive the pop-up message "unknown format?" instead the "please wait" one.

When the callback works I hear the voice with my credit, the quality is more than poor.
I'm roaming on TIM net and using the SonyEricsson Z1010 UMTS/GSM phone, with direct calling.