I signed up for the beta test and followed the instructions in n900-ipv6.garage.maemo.org.; i'm using the latest titan-kernel, edited 00_enable_apn_ipv6 file to reflect the ipv4 APN (using internet3.voicestream.com) and ipv6 APN.
'ifconfig' shows only "gprs0" and obviously no swimming turtles for me.

any suggestions where to begin the troubleshooting?