I have a problem with my OTRS 4 Appliance installation. At the Weekend it stopped working because of an Database error and now it´s not possible to start the postgresql service

Has anyone an idea what i can do?
1st error: Starting PostgresSQL 8.4 database server: main The PostreSQL server failed to satrt. Please check the log output:... failed! failed!
I checked the log output.
and there where 3 different failures.
1st one:
2015-06-29 00:10:23 CEST FEHLER: Wert zu lang für Typ character varying(3800)
2015-06-29 00:10:23 CEST ANWEISUNG: INSERT INTO article (ticket_id, article_type_id, article_sender_type_id, a_from, a_reply_to, a_to, a_cc, a_subject, a_message_id, a_message_id_md5, a_in_reply_to, a_references, a_body, a_content_type, content_path, valid_id, incoming_time, create_time, create_by, change_time, change_by) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17,
'2015-06-29 00:10:23'
, $18,
'2015-06-29 00:10:23'
, $19)
-----------------
2nd:
"2015-06-29 03:30:04 CEST LOG: konnte tempor?re Statistikdatei >>pg_stat_tmp/pgstat.tmp<< nicht schreiben: Auf dem Ger?t ist kein Speicherplatz mehr verf?gbar "
which means that there is not enough space, but there is enough space at my VM.

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3rd
2015-06-29 07:30:03 CEST FEHLER: konnte Relation base/16385/16769 nicht erweitern: Auf dem Gerät ist kein Speicherplatz mehr verfügbar
Thanks!
Johannes