Macro problem: unset wait_key; !do_script; set wait_key

[Ad. Teixera]

Hello,
This macro is working:
macro index <ESC>f  ":unset wait_key\n;!~/myScript\n;:set wait_key\n" \
   "menu for fetching mail"

this one works also, but it is not setting the wait_key at the end of the
macro.
macro attach <ESC>b ":unset wait_key\n|cat >/tmp/tmp.html; \
   opera --remote 'openURL(/tmp/tmp.html,new-page)' &\n; \
   :set wait_key\n" "Pipe to Browser"


I'm working with:
Mutt 1.5.17+20080114 (2008-01-14)
on a debian sid

Thank you,
Adriana