There's a caveat:

1. %FWSM-3-305006: Regular translation creation failed for protocol src interface_name:source_address/source_port dst interface_name:dest_address/dest_port

A protocol (UDP, TCP, or ICMP) failed to create a translation through the module. This message appears as a fix to caveat CSCdr0063 that requested that the module not allow packets that are destined for network or broadcast addresses. The module provides this checking for addresses that are explicitly identified with static command statements. With the change, for inbound traffic, the module denies translations for a destined IP address identified as a network or broadcast address. The module utilizes the global IP and mask from configured static command statements to differ regular IP addresses from network or broadcast IP addresses. If the global IP address is a valid network address with a matching network mask, then the module does not create a translation for network or broadcast IP addresses with inbound packets. For example: static (inside,outside) 10.2.2.128 10.1.1.128 netmask 255.255.255.128. Global address 10.2.2.128 is responded to as a network address and 10.2.2.255 is responded to as the broadcast address. Without an existing translation, the module denies inbound packets destined for 10.2.2.128 or 10.2.2.255, and logs this syslog message. When the suspected IP is a host IP, configure a separated static command statement with a host mask in front of the subnet static (first match rule for static command statements). The following static causes the module to respond to 10.2.2.128 as a host address: static (inside,outside) 10.2.2.128 10.2.2.128 netmask 255.255.255.255. static (inside,outside) 10.2.2.128 10.2.2.128 netmask 255.255.255.128. The translation may be created by traffic started with the inside host with the questioned IP address. Because the FWSM views a network or broadcast IP address as a host IP address with overlapped subnet static configuration, the network address translation for both static command statements must be the same.

I'm not sure if its with your specific version, might be...

Federico.