TDavid.contains(verse) does not work correctly

TDavid.contains(verse) often returns true for verses that aren't in Psalms.

Here is a test to show the problem:

public void testTDavidContains() throws Exception {
Book tdavid = Books.installed().getBook("TDavid");

Verse verse = VerseFactory.fromString("Prov 19:14");
assertFalse("TDavid contains not working correctly 1", tdavid.contains(verse));

verse = VerseFactory.fromString("Isaiah 55:1");
assertFalse("TDavid contains not working correctly 2", tdavid.contains(verse));
}