TYPO3 Core

I installed TYPO3 6.2 alpha2 on my server (tx_extensionmanager_domain_model_repository table is empty)

Go to the EM > get Extensions > "update now" Button and the ajax request call this Link:
"typo3/mod.php?M=tools_ExtensionmanagerExtensionmanager&tx_extensionmanager_tools_extensionmanagerextensionmanager[action]=updateExtensionListFromTer&tx_extensionmanager_tools_extensionmanagerextensionmanager[controller]=UpdateFromTer&tx_extensionmanager_tools_extensionmanagerextensionmanager[format]=json&tx_extensionmanager_tools_extensionmanagerextensionmanager[forceUpdateCheck]=1&_=1378728448325"

output of this link was:

"Fatal error: Call to a member function getUid() on a non-object in .../typo3/sysext/extensionmanager/Classes/Utility/Repository/Helper.php on line 251"

a Workaround with SQL query:
INSERT INTO `typo3_xxx`.`tx_extensionmanager_domain_model_repository` (
`uid` ,
`pid` ,
`title` ,
`description` ,
`wsdl_url` ,
`mirror_list_url` ,
`last_update` ,
`extension_count`
)
VALUES (
NULL , '0', '', NULL , 'http://typo3.org/mirrors.xml.gz', '', '0', '0'
);