Calling numbers with * in it

[DeepB]

Hello,

I use both T46G and T48G phones on an Askozia (Asterisk based) pbx.
I also use Gigaset DECT-Phones.

In Askozia call forwarding is enabled by calling 000023*116*120 (in this example forward extension 116 to extension 120)

This works flawlessly on my Gigaset phones, but unfortunately not on my Yealink phones. It starts the Call but nothing happens.

Any ideas?

Thanks
Daniel