Wow.... an odd request.
resetsp.bin was what the EZTeam used to use to update the EZ5 although not for a while (all the non EZ5i use 2.0 kernels and the EZ5i is on 3.0- they split them as it was not feasible to maintain them together*). Still the last one released was http://filetrip.net/f18751-ez5-resetsp-bin-1st-04-2009.html
*if you are on that old a kernel that you are still using resetsp.bin updating is not a matter of just overwriting the lot and you might have to update bootstraps if you are on the older devices or update the internal loader/firmware if you are on the EZ5i and that will be multipart for you (you will have to get to v12 or so and then update to v101 and then to the current versions). Say so if you do need some help here.
If you are using the newer kernels and the error is still there you might have found a regression and it will need to be fixed.