This is only useful if sleep by menu command works flawlessly ...
KWSleep for 10.7 - 10.9.x (10.10 not tested ...)
KWSleepLion.zip 272.25KB 7 downloads
Basically consisting of 2 shellscripts: sleep.sh is running by launchd every 30 s (directory: /Library/Scripts/KWS/), los.sh monitors changes in com.apple.PowerManagement.plist (add changed sleeptime in syspref to sleep.sh).
The installer includes a prog named EditKWSleep which is a "frontend" to change settings in the script. Obsolete for people with knowledge of shellscript syntax ...
Heres the manual of Edit KWSleep:
KWSleep Manual.pdf 172.48KB 2 downloads