NO CARRIER - again

thank you for your reply,

although i see your point that a kernel upgrade as well as a driver 
upgrade could cause problems, i was using the modem successfully under 
the same kernel (and only a slightly earlier version of the driver) just 
a couple of days ago, which suggests that it is something to do with my 
driver configuration or kernel configuration. i also have an Intel HDA 
sound card through which i can hear the modem getting stuck, but could 
it be this (or its driver) that is causing a conflict? also, are there 
any kernel options that are required by the modem driver or that are 
known to cause conflict?

thanks in advance.