If you are getting the following error when packaging up AIR app:
[java] Could not generate timestamp: Connection timed out: connect
means ADL cannot connect to Adobe to get the timestamp. Assuming you have internet connection it is worth checking if you don’t have to use a proxy to do so.
If you are using proxy, you need to configure JRE to use it as well and you do it in
[Adobe Flash Builder 4 folder]\jre\lib\net.properties
Simply set: java.net.useSystemProxies=true if you want to use the system proxy, or specify it manually. More instructions in the properties file.