Caulker impressed during a loan at the Liberty Stadium in the 2011-12 season.
Swans midfielder Leon Britton has been in contact with the Cardiff centre half since his move from London, saying: "I don’t know what sort of reception he’ll get (from Swansea fans). He was with us for a season, but albeit on loan. He wasn’t signed permanently to Swansea.
"It’s down to the Swansea fans what reception they want to give him. I still keep in contact with him, he’s a good lad and did very well for us.
"I texted him and said, “Get ready for the build up” because he is new to it as well. It’s going to start now. But he’s doing really well, he’s captain there when Bellamy doesn’t play so he’s doing really well."
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