According to a writer's guide grammatically, if a quote is truncated after a commas or a full stop, the comma or fullstop should be left in place with no intervening spacing.
Blah blah blah,...
Blah blah blah....
It's an interesting problem though. I think on it and get back to you:)
Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon