DB function failed with error number 1054 - Joomla! Forum - community, help and support

i had got v.2.5.4 running ok then, on moving live public_html, error...

jtablesession::store failed
db function failed error number 1054
unknown column 'gid' in 'field list' sql=insert `maygs_session` ( `session_id`,`time`,`username`,`gid`,`guest`,`client_id` ) values ( 'e05bce9e31765b6554a4d206ce19dfbf','1345621404','','0','1','0' )
fatal error: allowed memory size of 201326592 bytes exhausted (tried allocate 80 bytes) in /home/calvary1/public_html/j25/libraries/joomla/error/exception.php on line 117

live site - http://www.calvarychurch.org.uk
dev't site (with error) - http://www.calvarychurch.org.uk/j25

i have tried fixing etc no joy...
so have re-instated live site now.
please help...
ian


16-40pm
i have got dev't site working backup admi not work. when log in error...

fatal error: call member function login() on non-object in /home/calvary1/public_html/j25/administrator/components/com_login/admin.login.php on line 64


any ideas?