Async triggers

[Peter <peter@xxxxxxxxxxxxxxxx>]

Is this possible in PG somehow? Basically I need to call web service 
whenever new row is inserted in a table - the lookup takes time up to 
10-15 seconds. Obviously I cant do this inside trigger proc as that 
would delay inserts a lot. I suppose I could do a cron job to do 
webservice lookups periodically, but that involves delay and added point 
of failure (if cron process stops working for whatever reason). Ideally 
async trigger proc would be the solution, but it seems I cant do 
asynchronous execution in PG.

Thanks!
Peter