overwriting SEH and debugging

Hello,=0D
=0D
I am in situation that I have successfully overwrite SEH in some app. I k=
now that because when I am debugging this app I get exception ( access vi=
olation ) and then I can thanks to go to fs:[0] find out what is in first=
 SEH structure. =0D
=0D
I have overwritten this SEH by ordinary \xeb\x30\x90\x90 and address of P=
OP edi/POP esi/RET 8 instruction in shell32 module. I am wondering why wh=
en I press SHIFT+F9 in ollydbg I get "Debugged program was unable to proc=
ess exception". But when I overwrite address of handler in SEH by for exa=
mple: \x41\x42\x43\x44 then when I press SHIFT+F9 I get that 0x44434241 c=
annot be accessed - so next exception - as it should be. Where is a probl=
em?=0D
=0D
opexoc