Seems to indicate that they are unbuffered dimms, and can exist in ddr1/2/3 formats. I know that this doesn't help your question, but it does tell you that just knowing it is udimm is not enough, you also need to know the ddr rate.
looking at this: http://www.dell.com/uk/business/p/poweredge-t110-2/pd
it seems to indicate that the T110 II takes DDR3, with an intel C202 chipset, so the question then becomes what does the C202 chipset take?
The UK site is listing that memory package as being at £2k so maybe $2.5K? They are Low Voltage DIMMs, although i'mnot sureif that is simply preferred or required.http://ark.intel.com/chipset.aspx?familyID=53099
doesn't help, but an email to intel might.