[GENERAL] Alter Column from inet to inet[]

[Alex -]

Hi,I need to change a column type from inet to inet[] but the alter command 
always gives me the following errors
ERROR:  column "access_ip" cannot be cast to type inet[]
ALTER TABLE users ALTER COLUMN access_ip SET DATA TYPE inet[] USING 
access_ip::inet[];
Tried various but no luck. Couldn't find anything in the manuals either.
Can anyone point me in the right direction or tell me what's wrong with my 
statement.
Thanks for any help.
Alex