unable to deploy a war file to oracle application server 10g

[Ahmed M. Omar]

i am developing a web application,using struts framework and Eclipse IDE and OC4J as a servlet container when i export a war file and trying to deploy this war on Oracle OAS 10g the following message appears :

Failed to deploy web application "aoas_new". Failed to deploy web application "aoas_new". . File C:\WINDOWS\TEMP\dir48668.tmp\aoas_new.war is not a jar file.
Resolution:

Base Exception:
java.util.zip.ZipException
invalid END header (bad central directory offset). invalid END header (bad central directory offset)

can any one tell me the reason or the solution of this problem?

thanks in advance