xo rear mech problem

having bent my rear mech hanger and replaced it I now find the bolt to fix the mech to the hanger is totally seazed.
Any ideas on how do undo it?

the pivot bolt. Easy solution – buy a short cage x9 for me and have my long cage x9

suprisingly enough undo the C clip on the back of the bolt and it will fall out.

my specialist subject again!!!
You can get the entire bolt out of the mech.
On the inside (to the frame) there is a metal circlip that holds the bolt and B screw bit in place. Remove circlip (akward) remove bolt – may require judicous use of force (good clout with a hammer).
May have a spare bolt somewhere amongst my collection of bits
ANY SRAM MECH BOLT WILL DO THEY ARE UNIVERSAL
CRC do one cant rememebr price
E-mail if you want more info

cheers. will have a go at the circlip