Contribution types starting with lower case letters create API error

Having a contribution type starting with a lower case letter, CRM_Contribute_PseudoConstant::contributionType () returns all contribution types with lowercase letters. However, the API checks the contributiontype with an "ucfirst ( $value )" (line 320 of api/v3/Contribution.php):

$contributionTypeId = CRM_Utils_Array::key ( ucfirst ( $value ), CRM_Contribute_PseudoConstant::contributionType () );

This results in a NULL, and any contribution updates will fail with "Invalid Contribution Type".

Eigther, ucfirst should be removed, or all contribution types should be converted to ucfirst, too.