UK (currency GBP; exchanges LSE, VALUE)
Belgium (EUR; SBVM)
France (EUR; SBF)
Germany (EUR; SMART, IBIS, FWB, SWB)
Italy (EUR; BVME, not supported at this time by IB)
Netherlands (EUR; AEB)
Spain (EUR; BM, not supported for simulation account)
Sweden (SEK; SFB)
Norway (NKK; SFB, not tried so far)
Switzerland (CHF; EBS, VIRTX)
Make sure that you submit your UK stop/limit price in pennies.