Dear Maintainer,

When xflock4 is run it should activate locking in the screensaver.

However, the current result is:

$ xflock4
/usr/bin/xflock4: 52: arithmetic expression: expecting primary: "2**31
- 1"

This is because $((2**31 - 1)) is evaluated in an argument to attempt
to disable the dbus-send reply timeout.  However, /usr/bin/xflock4
uses #!/bin/sh, which is dash (not bash) on Debian.  dash is POSIX
compliant and does not support the "**" exponentiation operator.  This
is probably a bash-ism - indeed, if I modify the script to use
#!/bin/bash, the script works.

The script might as well pass the fixed value 2147483647 instead of
trying to be clever.

Thanks...