As reported in BUGTRACK you can DoS rxvt 2.6.1 with echo -e "ESCAPE[4;65536;65536t" (where ESCAPE is \033) rxvt seems to consume all memory and machine becomes unusable for a while. rxvt-2.6.3 seems to correct this bug, so you should upgrade the package. -Jarno
i have fixed the bug. Thanks for your report. Than