I'm not at all surprised that a company is offering VoIP service to the Nokia E Series audience.
What I am surprised about is their claims, for as of now I know of no way to work around NAT Traversal issues inherent in the E Series, which they need to do to get SIP based VoIP to work for both inbound and outbound calling.
I also don't know what browser they are using, for the Nokia browser crashes in T-Mobile and other hot spots when hit with the Java script probe.
I know from my chats with SipPhone founder Michael Robertson that his team has been helping Nokia understand the NAT/Traversal issue, and also that since I have SipPhone working for outbound calls (thanks to PhoneBoy) that half the battle has been won.
I also tried to shortcode to the address, but had no success, but that's likely due to my being in the USA.
If these folks can get me up and running, I'll gladly blog about the results.
Update--> Something must be up though, as TeleGeography is reporting that SingTel is working on a similar play.