undefined procedure error in iRule

when CLIENT_ACCEPTED {
    if { [IP::addr [IP::remote_addr] equals 172.22.64.0/24] } {
        snat 172.22.64.68
        log local0. "SNATTed of SiteB"
        pool Test_pool
    } elseif { [IP::addr [IP::remote_addr] equals 2.2.2.0/24] } {
        snatpool NAME_OF_SNAT_POOL
        pool Pool_Name
        log local0. "SNATTed of SiteA"
    } else {
        pool Normal
    }
}

There was a closing curly bracket missing at the end (related to the event).

Are you dealing with a large number of client IPs to translate with different SNATs? Perhaps the 'switch' command will be a better choice: