"char" vs. "signed char" vs. "unsigned char" in rule 10.5

[Lundin]

MISRA did state somewhere on these boards that 10.5 should be regarded as an exception to 10.3.

My static analyzer (LDRA) gives warning for violation of 10.5 in the first case but for 10.1 in the second case.
This seems like a sensible solution, as 10.1 and 10.5 overlap. As long as the tool gives some kind of warning...