This means that the list of jars that need to be scanned for TLDs during servlet statup time contains non-existent jar files. The list of jars are computed from the TLDs bundled in the jars, and the jar files that are specified in the manifest class-path of those jars. It is likely that Manifest class-path of some of the jars contain jars that no longer exist. However, you can safely ignore such warning, especially if you are not the owner of these jars.
It would be helpful if the warnings tell you which jars that has bad manifest class-path.
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