Xtend Antenna

hi,
I have just received a sample Fastract Xtend FXT002. By using the antennas of old fastract supremes, i get +CSQ: 99,99 response to my AT+CSQ commands. Fastract Supreme antenna is not suitable for Fastract Xtend? Should i buy an other type of antenna? Or is there anything i am missing?

Thank you.

I am having same problem with the Xtend I have received, Using the Supreme Antenna I read +CSQ: 99,99 in response to at+csq.

Yves