I have ZTE -AC2726 USB Modem. In Ubuntu 'Saucy' its being detected only as 'stroage device'. I have checked the Modem in other distros, like, Debian Wheezy_xfce, fedora18_xfce, and in Arch_gnome and the moded is detected as Modem.
In all the three distros I have tested my Modem the device ID from 'lsusb' is 12d1:1001 but on Ubuntu its 12d1:1446 and never changes.
In 'Saucy' I have uninstalled 'usb-modeswitch' completely and reinstalled it but without any improvement in the status. Its NOT switching to Modem. I borrowed two other modems from my friends and tried it on ubuntu. They don't work neither. However no problems on other mentioned distros.
Since this is happening only in Ubuntu, I was wondering if its a bug in the 'usb-modeswitch' package or some other package, library or dependency related to it, which Ubuntu ships.
I am not sure if its a bug. If fellow Ubuntu users can confirm this.. then perhaps it is a bug and needs to be reported.