Given the following invalid action: <fmt:bundle basename="some.Resources"/> Result: java.lang.NullPointerException at org.apache.taglibs.standard.tag.common.fmt.BundleSupport.doEndTag(BundleSupport.java:137) Since this is a syntax error, the TLV should be catching this. Additionally, if the TLV did miss it, an NPE is not an ideal result.
Fixed. Note that this is not a syntax error, though (see 2.5: "If an action accepts a body content, an empty body is always valid, unless explicitly stated otherwise".). <fmt:bundle basename="some.Resources"/> is perfectly valid, except that it should not do anything instead of throwing a NPE. If this were a syntax error, the spec would have to clearly specify it as such.