cast iron soil pipe/ pvc branch?

[cdel2005]

hi guys,
are there any coupling available which can join cast iron to pvc for a soil pipe? names of products if any please if not how difficult is replacing a cast iron soil stack?

if i was to replace all of the existing cast iron soil pipe,would i have to dig down to the sewer main,cut the clay pipe,add a clay to pvc coupling get it checked by local authority is this right?
cheers

 

[picasso]

not the prettiest of connectors but effective
http://www.fernco.com/plumbing/flexible-couplings

 

[kirkgas]

i prefer "timesaver" joints, they seem more robust