It is possible, although from reading the comments here, people have no idea how the technique works, in both instances. Nor have they an idea regarding the differerence of "viable semen" and "material suitable for extracting a DNA profile from".
Crudely put, if you've got a condomfull of jizz, you have more than enough material to make a DNA profile. DNA does deteriorate over time, but contrary to popular opinion, if a sample is not "consumed" by infection with microorganisms, it actually lasts a very, very long time, even if fragmented. ( which is why DNA typing of preserved/contained (pre)historic DNA is possible to begin with.)
Spermicide does not destroy DNA , as a couple of peeps here seem to think. It renders sperm cells immobile, which is a different matter altogether.
Ask yourself if you would voluntarily put a substance on/in your fiddly bits that would penetrate cells, and destroy DNA... ( a mix of industrial-stength degreaser and bleach would be the closest equivalent you could cook up in your kitchen, other "simple stuff" like toluene and it's nastier cousins work just fine..) .... I thought not.
With modern PCR machines getting a profile from a "fresh" DNA sample is a matter of hours. Hell, doing it by hand if you've got fresh DNA to extract and a stock of the proper restriction enzymes takes no more than half a day.
The delays in confirmation for judicial purposes lies more in getting *the rest* of the samples. Family members for paternity cases. One or more DNA samples of the suspect from other locales in the case of [enter suspect here].
Unless the Man already had Assange's DNA profile in a database, there would be no way to tell the DNA sample profile from the average Joe in the street.
Even as oversimplified as above, it's clear that it is quite possible to get a proper DNA profile from a condom, even if it's months old, and simply stuck to the bottom of the bin, instead of following the more usual sewer rollercoaster route. So if either condom providedis *the* condom, the DNA profile should be clear and unequivocal, since the forensic plods would have to have had either corroborating samples, or a proper DNA database profile to compare it against.
There is such a thing as "proper evidence" after all, and while commentard (anti)rage may rule here, the swedish forensics working on the sample *should* not even know whose sample it is they're processing. For lab purposes you simply need a unique processing number, which would tie to the actual file at a completely different level. ( which would also be another reason why things "take long". Unless it's an official rush job, such profiling goes on a first come, first served basis, and the queue might be long, as there aren't *that* many DNA profiling machines in any police force.)
Just a couple of things to ..unconfuse.. matters.
Oh, and Paris, because this thing is as whipped up as her Sillycones.