If you are in the UK take it back to where you bought it for a refund as it is not fit for purpose.
(If you are not write to the Fujitsu-Siemens Chief Exec in your country.)
A laptop power connector is designed to take many thousand of connections and disconnections over its life time (and a certain amount of abuse as well).
Your local computer shop was talking rubbish. I used to sell laptops for a well known computer company (not F-S) and NEVER saw a broken power connector on one of ours. I am sure that this does happen but not as much as your computer shop says or maybe they just sell cheap and nasty computers. (Which your one isn't.)
t
September 2008