I too had this very same problem. In fact last week, after sitting outside at work, the car would stall as soon as I touched the throttle, let alone placing it into gear

I changed the oil last night from Mobil 1 10W-30 to Mobil 1 5W-30 and changed to a Puralator PureOne oil filter. This filter, however, does not have the extra drain back valve that the Volvo filter has. Anyway, the car started right up this morning and did not stall when I placed it into gear. Now, this is only one startup and only anecdotal evidence so I will have to see if it helped cure the symptom, but not necessarily the problem.

The car is sitting outside in Minneapolis today, with a predicted high of 21°F. I'll have to wait 'till tonight to see if the starting is any better.

A side note:

I have used the Mobil 1 oil filter on my Toyota MR2 (79k miles) and after 2k miles the oil was still translucent and amber colored. Mobil also claims a high filtering efficiency on the multi-pass filtering test. I could not get the Mobil filter for the Volvo, so I’m trying the PureOne to see if it works better than the Volvo filter.

http://www.pureoil.com/pureone.htm