I see. All library jars need to be placed in the lib directory of the ear (instead of at the ear root) according to the EE spec. You can try to repackage your app according to the EE spec, or you could use this flag to deploy your app (where we try to preserve backward compatibility of the v2 behavior, this is not available in preview build and only available in later versions of the v3 build):
asadmin deploy --property compatibility=v2 foo.ear
For the latest build, I was referring to this (right now the latest build is b70):
http://download.java.net/glassfish/v3/promoted/
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