Template export doesn't work

When exporting any of the default Zabbix templates (old ones, without discovery), I get empty xml file. Frontend shows a message that export was successful, and there are no details in this message.

There is an error in Apache log file:
[Thu Apr 19 19:18:02 2012] [error] [client 192.168.150.1] PHP Fatal error: Argument 1 passed to CConfigurationExportBuilder::formatApplications() must not be null, called in /usr/share/zabbix/include/classes/export/CConfigurationExportBuilder.php on line 68 and defined in /usr/share/zabbix/include/classes/export/CConfigurationExportBuilder.php on line 473, referer: https://zabbix/zabbix/templates.php?ddreset=1&sid=facd07ffb9d5bfa0

However, if I comment out lines with applications, discovery_rules and screens in /usr/share/zabbix/include/classes/export/CConfigurationExportBuilder.php near line number 68, export works.