synproxy problem

[duncan]

I tried to implement synproxy the other day and found that some of our 
clients couldn't connect to our http servers.

        pass in quick on $ext inet proto tcp \
        from any port $safe to $httpdservers port http \
        flags S/SA synproxy state
I'm including my http server rules just in case my problem is the has 
something to do with them.

        pass in quick on $ext inet proto tcp \
        from any port $safe to $httpdservers port http \
        flags S/SA keep state
        pass out quick on $ext inet proto tcp \
        from $httpdservers port http to any port $safe \
        flags S/SA keep  state
Do I need to change the flags and state declaration to something other 
than S/SA keep state, should it be SA/SA keep state?