Alan brought in Pavel from Portsmouth initially for a month on Thursday following the departure of Rami Shaaban, who himself was a loan signing for the same period from Arsenal.
Explaining the move, Alan says:
"We were looking for a goalkeeper with a bit more experience; Pavel is Tomas Repka's big friend so I thought this was a good thing to happen as Tomas has been important to us this year.
"Their relationship would be fruitful if they have to play together.
"Steve has done terrific and he will have a top quality goalie sitting behind him on the bench now.
"That will give him confidence.
"I am pleased with him and I am sure he and his family are pleased with him as well - because he has done magnificently."
As for promising custodian Chris, who has trained with the Hammers, Alan says:
"Chris is doing very well and he is a great goalkeeper who we are going to constantly monitor.
"But we are still going down the road with Steve Bywater at the moment.
"We have to look to see where Steve is at the end of the season to see what kind of goalie we are going to bring in, whether it is an experienced one to be next to him, young competition, or whatever.
"We won't know that until we have seen Stephen over a period of 10 or 15 games or so."
West Ham's other keeper is David Forde, who played in the reserves midweek.