Answer received on the Postgresql IRC channel by scampbell and indigo.

[sql]
SELECT array_to_string(array(SELECT REPLACE(column, ',', '\,') FROM sometable), ',')
[/sql]

now you have a rll encoded output, , are imbedded data commas and , are field separators. No data corruption on the transfer just turn the , back into , on the receiving side.

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As indigo noticed the character would also have to be escaped.