Error while indexing a perforce repository

2010-08-09 14:07:55,560 DEBUG [InitialPinger1] fisheye.app P4CliUtils-dumpCommandLine - [local:1666/] Executing /data/p4/bin/p4 -p local:1666 -u p4user -ztag fixes //...@31622,31881 
2010-08-09 14:07:55,769 DEBUG [InitialPinger1] fisheye.app P4Process-finish - Exception processing command /data/p4/bin/p4 -p local:1666 -u p4user -ztag fixes //...@31622,31881 
java.lang.NullPointerException
	at com.cenqua.fisheye.perforce.client.P4Client$5.processGroup(P4Client.java:206)
	at com.cenqua.fisheye.perforce.client.P4ZTagExtractor.processLine(P4ZTagExtractor.java:43)
	at com.cenqua.fisheye.perforce.client.P4OutputLineProcessor.processOutput(P4OutputLineProcessor.java:32)
	at com.cenqua.fisheye.perforce.client.P4Exec$4.processOutput(P4Exec.java:180)
	at com.cenqua.fisheye.perforce.client.P4Process$2.doTask(P4Process.java:130)

public void processGroup(Map<String, String> group) {
                // This is a fix of a job
                String jobName = group.get("Job");
                long changeId = Long.parseLong(group.get("Change"));
                long fixDate = Long.parseLong(group.get("Date"));
                String user = group.get("User");
                P4Fix fix = new P4Fix(jobName, changeId, fixDate, user);
                P4ChangeList change = changeLists.get(changeId);
                change.addFix(fix);