Vectors.asm, RAM_THROW extension:

		bcs.s	\NotAFunctionCall
		cmp.l	#kernel::EndSharedLinker,a1	; Compare the address. Is-it inside the PreOs kernel routine?
		bhi.s	\NotAFunctionCall
-			btst.l	#5,d1			; Called in supervisor mode ? 
+			btst.l	#13,d1			; Called in supervisor mode ? 
			beq.s	\UserMode		; No 
				move.w	d1,6*4(sp)		; Rewrite SR (need another return adress on the stack) 
				move.l	a1,6*4+2(sp)		; Set the ramcall ptr as the return adress of the handler 

I had writen '5' because I tested the bit in the upper byte of the SR inside the stack ... I didn't see that when you optimized this part of the routine. Sorry for not having catch that...

In my programs (man & eexec), this doesn't produce a bug, because the bit 5 of the SR is not used (so it's 0), and I always call the handler when in user mode.