Sporadically now dial-up on 2.6.1 and 2.6.1-mm3

This was OK in 2.6.0. After updating to 2.6.1 I can dial into provider, I am authenticated and interfaces set up but apparently no packet ever flows over this connection. Same in 2.6.1-mm3. Sometimes (very rarely) it works but now I have to boot into 2.6.0 to send this.

There was similar problem somewhere around 2.5.70; I do not know specific fix as it went away after updating kernel version.

Please let me know what information is needed and how to collect it (I have close to zero knowledge about networking in kernel)

TIA

-andrey