Faxes doesn't being received in lion while the mac is sleeping

Question

i am using  fax in my macs.
sending faxes is ok.
the computer is ready to recieve faxes only if the mac is not sleeping
this is the same in two computers(mbair) and  in  the pax program of the lion's or in page sender fax program.
means : the problem is inherent to  the imposibility of the mac to detect fax ring while sleeping.
i wonder if sombody else is sauffering those manifestations and i need an advice to solve this.

Answer 1

Sleep mode stopped working on both my MacBook Pro's after upgrading to Lion. Never had issues before.
To check if some process is keeping your Mac from falling asleep you can run the command "pmset -g live" in a Terminal. Now if some process is preventing sleep mode its process number is displayed (between rounded brackets) after the corresponding line in the pmset output. If no process is preventing your Mac entering sleep mode then something else is wrong. Can't tell you what that is cause I don't know.
pmset -g live
Active Profiles:
Battery Power                    -1
AC Power                    -1*
Currently in use:
womp                    0
halfdim          1
sms                    1
panicrestart          15
gpuswitch          2
hibernatefile          /var/vm/sleepimage
networkoversleep          0
disksleep          1
sleep                    15
hibernatemode          3
ttyskeepawake          0
displaysleep          7
acwake                    0
lidwake          1
From this result there is no process preventing the Mac from falling asleep. Still on my MacBook it doesn't enter sleep even if no process is preventing it.
The line you should be looking for is the line with the keyword "sleep".