If you receive the followin error:
EXECUTE permission denied on object 'proc_putObject', database 'SharePoint_Config', schema 'dbo'.
EXECUTE permission denied on object 'proc_putDependency', database 'SharePoint_Config', schema 'dbo'.
EXECUTE permission denied on object 'proc_putDependency', database 'SharePoint_Config', schema 'dbo'.
EXECUTE permission denied on object 'proc_putDependency', database 'SharePoint_Config', schema 'dbo'.
EXECUTE permission denied on object 'proc_putDependency', database 'SharePoint_Config', schema 'dbo'.
when you try to activate a SharePoint 2007 Feature through the http://yoursite/_layouts/ManageFeatures.aspx?Scope=Site url, it's probably because your user probably doesn't have enough rights on your Sql Server Database.
Try to activate the feature using the stsadm command
stsadm -o activatefeature -name yourfeaturename -url http://yourserver/