This doesn't mean its been flashed to virgin mobile. It means that its running virgin mobile firmware, so the sprint towers see it as a virgin mobile phone and you'll get less tower priority, and you'll likely get dropped data and just a crappy connection in general.
Edit... If the phone was flashed over to VM, that would be an easy fix. Your problem runs deeper. If you want it fixed, be ready to use some linux.
not quite. Virgin mobile is now selling sprint branded EVO 3Ds in virgin mobile boxes. Everything is virgin but the phone says sprint. I bought a virgin EVo 3D that looks just like a sprint phone with the sprint logo on the bezel but it has all virgin mobile software and bloatware. they are doing this to keep up with the demand for the phone.
If it is a sprint phone flashed to virgin mobile then all you have to to is follow the to fix the VM ICS leak. there is one on the XDA website.
if it is a Virgin mobile phone, there is also a way to flash a sprint stock ROM.
If you go to about phone --->phone identity ------>phone name should be HTC EVO V.
V for virgin mobile. If it doesnt say that it is a tru sprint phone. (unlsess it says something completely different then it has been changed from the stock ID) They all work on on the sprint cdma snetwork but as stated earlier virgin gets a lower tower prioirty and throttled data speeds... Virgin's 4G is about as fast as Sprints 3G and Virgin 3G is about as fast as tmobile edge (even a bit slower)...
My EVo 3D V has a sprint ics ROM..meanrom 2.6 installed by me. it came virgin stock (sprint TV, Sprin acct info, Sprint bloatware etc.) but it is a virgin phone from day one.
It actually looks like it is a refurbished phone due to some minor defects.....