gloox is fully compliant to XMPP Core and almost (see below) fully compliant to XMPP IM. The following are some of the supported features:

• TLS and SASL
• roster management
• privacy lists
• SRV lookups
• server certificate verification
• support for xml:lang i18n

Additionally, the following XEPs are supported:

• XEP-0004 Data Forms: complete
• XEP-0012 Last Activity: complete, experimental
• XEP-0013 Flexible Offline Message Retrieval: complete
• XEP-0022 Message Events: complete
• XEP-0030 Service Discovery: complete
• XEP-0045 Multi-User Chat, complete
• XEP-0047 In-Band Bytestreams: complete
• XEP-0048 Bookmark Storage: complete
• XEP-0049 Private XML Storage: complete
• XEP-0050 Ad-hoc Commands: command provider complete
• XEP-0054 vcard-temp: complete
• XEP-0055 Jabber Search: complete
• XEP-0065 SOCKS5 Bytestreams, TCP mode only for now
• XEP-0077 In-Band Registration: complete
• XEP-0078 Non-SASL Authentication: complete
• XEP-0083 Nested Roster Groups: complete
• XEP-0085 Chat State Notifications: complete
• XEP-0092 Software Version: complete
• XEP-0095 Stream Initiation, complete
• XEP-0096 File Transfer, IBB not integrated yet
• XEP-0114 Jabber Component Protocol: complete
• XEP-0138 Stream Compression: complete
• XEP-0145 Annotations: complete
• XEP-0170 Recommended Order of Stream Feature Negotiation
• XEP-0201 Best Practices for Message Threads

The following XEPs are supported by simple wrappers:

• XEP-0027 Current Jabber OpenPGP Usage
• XEP-0066 Out of Band Data
• XEP-0091 Delayed Delivery (old spec)
• XEP-0153 vCard-Based Avatars
• XEP-0203 Delayed Delivery (new spec)

It is known to run at least on Linux, *BSD, MacOS X, SkyOS, Syllable and Win32 (both MingW and MSVC). There also is experimental support for WinCE/Mobile.

Not supported but formally required by XMPP IM:

• End-to-end object encryption as defined in RFC 3923 (End-to-End Object Encryption in the Extensible Messaging and Presence Protocol (XMPP)): there are no other implementations of the spec
• handling of addresses that are encoded as "im:" URIs: this is better handled by client implementations