The background of the problem is: I am building up a trigger on account which will be triggered when an account is deleted. During execution it will invoke some webservices. But while deleting an account the trigger throws an exception 'System.CalloutException: Callout from triggers are currently not supported'. I think it means that webservices can not be invoked from a trigger.
One possible approach to resovle this issue is using @future annotation for methods invoking webeservice(s). Does any body knows any other solution?