Cleared for a night visual approach to Runway 35L at DEN; the flight crew of an A319 descended prematurely; exiting the Class B; going below the MVA and triggering the EGPWS TERRAIN warning.

Narrative

We were inbound to Denver in the early morning on the first day of daylight savings; still very dark with a low overcast below us obscuring the ground. Initially cleared to CHOLA on the ILS 35L at 9;000 FT. The field was called in sight following the query from TRACON and the flight was cleared direct DYMON for the visual. Our position was offset 2-3 miles right of the LOC and roughly 12-14 miles from DYMON. The ILS was tuned and a good ident verified. I set 7;000 for DYMON and the Captain began an easy descent to 7;000.Despite a good ident; the glide slope indication was approximately one dot above us and wandering slightly. ATC called stating we were below the MVA and below the Class B airspace. 1-2 seconds after the ATC call; the 'TOO LOW; TERRAIN' warning went off. The Captain added power; initiated a climb and called for 8;000 to be set in the ALT window. Pilot not flying set 8;000 and noted the Radio Altimeter climbing through 1;600 as we passed roughly 7;400. The Captain leveled at 8;000; 4-5 miles from DYMON; the glide slope reset to a below glide slope indication and the flight proceeded to land without incident.