Fehler DBI CONNECT: FATAL: sorry, too many clients already

Software error:

Can't call method "do" on an undefined value at webform.pm line 1956.
 at webform.pm line 1956
	main::db_do('undef', 'SET TIME ZONE LOCAL') called at webform.pm line 1848
	main::db_connect('klartext_red') called at /usr/local/httpd/htdocs/klartext.de/cgi-bin/klartext_main.pl line 118

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