Thank you for your attention Michael.
I dont get any log like class not found error!
And yes I add library jar file to platform.xml:
<?xml version="1.0" encoding="utf-8"?>
<platform xmlns="http://ns.adobe.com/air/extension/28.0">
<packagedDependencies>
<packagedDependency>pushe.jar</packagedDependency>
</packagedDependencies>
<packagedResources>
<packagedResource>
<packageName>co.ronash.pushe</packageName>
<folderName>pushe-res</folderName>
</packagedResource>
</packagedResources>
</platform>
and I see the jar file and its resources in .ane file.