Syntax Translation from v4.1 to V9.1

This should get you going

...
} elseif { [HTTP::uri] starts_with "/Data/uplink" } {
  if { [matchclass [IP::client_addr] equals $::vendors] > 0 } {
    pool P_DATA
  } else {
    discard
  }
}

You might want to convert the elseif line to

} elseif { [string tolower [HTTP::uri]] starts_with "/data/uplink" } {

if you want a case independent match.

Also, If your vendors list is an address list containing netmasks (and you have not upgraded to BIG-IP v9.0.3 or higher), you might want to check out this thread as well for a known issue with matchclass and comparing network addresses with netmasks.

http://devcentral.f5.com/Default.aspx?tabid=28&view=topic&forumid=5&postid=1235

Click here

-Joe