Sibling jars referenced via Class-Path manifest entries are not visible to each other

Issue

Our EAR has the following structure:

Folder: <appname>.ear
    Folder: <appname>.war
        Folder: META-INF
            File: MANIFEST.MF - this contains a Class-Path: jar1.jar jar2.jar ... jarN.jar classes
    Folder: <appname>_ejb.jar
        Folder: META-INF
            File: MANIFEST.MF - this contains a Class-Path: jar1.jar jar2.jar ... jarN.jar classes
    Folder: META-INF
    Folder: classes
        Folder: com
            Folder.... 
    File: jar1.jar
    File: jar2.jar
    ...
    File: jarN.jar

Wed need to have an arrangement of classloaders in such way that all the classes are being "shared". They fail with a "java.lang.NoClassDefFoundError: org/apache/oro/text/regex/MalformedPatternException", which is included in one of the jarN.jar mentioned (oromatcher jar, which is a perl5 compatible regex lib). I checked with all the Class-Path settings, oromatcher is included in the list.