Wireshark 1.3.2 beta is available for download at http://www.wireshark.org/download.html

Wireshark is the world’s foremost network protocol analyzer, and is the de facto standard across many industries and educational institutions.

• Deep inspection of hundreds of protocols, with more being added all the time
• Live capture and offline analysis
• Standard three-pane packet browser
• Multi-platform: Runs on Windows, Linux, OS X, Solaris, FreeBSD, NetBSD, and many others
• Captured network data can be browsed via a GUI, or via the TTY-mode TShark utility
• The most powerful display filters in the industry
• Rich VoIP analysis
• Read/write many different capture file formats
• Capture files compressed with gzip can be decompressed on the fly
• Live data can be read from Ethernet, IEEE 802.11, PPP/HDLC, ATM, Bluetooth, USB, Token Ring, Frame Relay, FDDI, and others (depending on your platfrom)
• Decryption support for many protocols, including IPsec, ISAKMP, Kerberos, SNMPv3, SSL/TLS, WEP, and WPA/WPA2
• Coloring rules can be applied to the packet list for quick, intuitive analysis
• Output can be exported to XML, PostScript®, CSV, or plain text

[From http://www.wireshark.org/]

An updated version of Wireshark has been released – 1.2.4. Full details are available in the release notes.

It is available in the following formats:

• Windows Installer (32-bit)

• Windows Installer (64-bit)

• Windows U3 (32-bit)

• Windows PortableApps (32-bit)

• OS X 10.5 (Leopard) Intel .dmg

• OS X 10.5 (Leopard) PPC .dmg

• Source Code

from the download page.