If I switch from  maximize my rxvt from rows 24; columns 80;  to rows 86;
columns 262; mutt segfaults :)

(gdb) bt
#0  0x5 in ?? ()
#1  0x4004f251 in SLcurses_wrefresh () from /usr/lib/libslang.so.1
#2  0x8058500 in strcpy () at ../sysdeps/generic/strcpy.c:31
#3  0x8059e42 in strcpy () at ../sysdeps/generic/strcpy.c:31
#4  0x806cdfc in strcpy () at ../sysdeps/generic/strcpy.c:31
#5  0x40234e21 in __libc_start_main (main=0x806c210 <strcpy+132976>,
argc=1, 
    ubp_av=0xbffffb24, init=0x804acc0 <_init>, fini=0x80a340c <_fini>, 
    rtld_fini=0x4000df94 <_dl_fini>, stack_end=0xbffffb1c)
    at ../sysdeps/generic/libc-start.c:111