These are the existing message bundle keys for FileEntry:

org.icefaces.ace.component.fileEntry.UPLOADING
org.icefaces.ace.component.fileEntry.SUCCESS
org.icefaces.ace.component.fileEntry.INVALID
org.icefaces.ace.component.fileEntry.MAX_TOTAL_SIZE_EXCEEDED
org.icefaces.ace.component.fileEntry.MAX_FILE_SIZE_EXCEEDED
org.icefaces.ace.component.fileEntry.MAX_FILE_COUNT_EXCEEDED
org.icefaces.ace.component.fileEntry.REQUIRED
org.icefaces.ace.component.fileEntry.UNKNOWN_SIZE
org.icefaces.ace.component.fileEntry.UNSPECIFIED_NAME
org.icefaces.ace.component.fileEntry.INVALID_CONTENT_TYPE
org.icefaces.ace.component.fileEntry.PROBLEM_WITH_CALLBACK

The existing FileEntry properties for overriding these are:

String maxTotalSizeMessage
String maxFileSizeMessage
String maxFileCountMessage
String requiredMessage

Definitely we should add one for successMessage and arguments could be made for invalidMessage, unknownSizeMessage, unspecifiedNameMessage, invalidContentTypeMessage, problemWithCallbackMessage. Although we haven't yet added the feature for specifying invalid contentTypes.