@Mike or
@M3E6 See if setting any jail related parameters to 0 will help this player, we tried doing so in-game but it didn't help. (Ma_Ro)
also HabaDaba i strongly advise using a clean version of San Andreas (by clean i mean actually clean, not 1 or 2 mods, 0 mods)
if it still occurs, post back in here.
EDIT: seen you ingame as HabaDaba, and seeing as you have placed a report, i'll assume you are able to spawn in-game as of now.
Closing topic, if the issue arises again, at least you know now what has fixed it.