It can be difficult, this one - any chiselling is likely to break off bits from the salt glaze soil pipe. As the loo pan seems to be loose, remove it completely by twisting it to and fro. Plastic pan connectors (B&Q etc) have rubber sealing fins that will seal into the salt glaze, so maybe you'll be able to leave the cement alone. Most loos these days have a 'P' trap outlet but there are plastic connectors that will sort you out.
John, March 2008
