Today I got the new modem from my broadband operator and this wasn't support by usb-modeswitch. Looking at the source code it seemed quite trivial to add support for it and I then got it working using the following configuration file, saved at "/etc/usb_modeswitch.d/12d1:1c0b" with:

#######################################################
# Huawei E173s

DefaultVendor= 0x12d1
DefaultProduct=0x1c0b

TargetVendor=  0x12d1
TargetProductList="1c05,1c08"

MessageContent="55534243123456780000000000000011062000000100000000000000000000"

WaitBefore=1

After that, re-plugging the adapter was enough to get it properly detected and working.

Update: I have sent this information to upstream author to try to get it into next release.

Update: I updated the configuration to my current one that is more stable