Lock & Unlock the screen via WLAN - Keyboard
You may be able to work something together in automator but I am not too familiar with that app.

I would check and see if you have wake for network access on. 
In System Preferences->Energy Saver there is a checkbox to "wake for network access". If that is unchecked it is unlikely your computer will respond since I believe that app is based on Networking

[UPDATE]: Doing a quick search it appears other users are experiencing this issue with synergy and lion. take a look here