The most recent software version available for the AT&T (SBC) Speedstream 5100b and 4100 modems is 1.0.0.53. As it has been several years since the last software update was issued and Siemens has apparently exited this aspect of the modem business by forming a JV with Nokia, it seems unlikely that any more updates will be forthcoming.
The most recent and only software version for the Speedstream 4100b modem is 1.0.0.63. That is the factory-issued software.
