Xenos Group, Inc. - Provides data and electronic document transformation solutions. - http://www.xenos.com/
TEXTML - native XML database server for content search and retrieval, supports WAP - http://www.ixiasoft.com/
OpenLink Virtuoso - A cross-platform, Internet data integration server, implementing native XML storage, web, file, and database server functionality and universal data access middleware as a single server solution. - http://www.openlinksw.com/virtuoso/
X-Hive/DB - XML Database in form of a Java-based persistent DOM implementation. - http://www.xhive.com/
Infonyte - XML database built on a PDOM and a XQL engine. - http://www.infonyte.com/
Xyleme - Dynamic data warehouse that is an indexed XML repository capable of answering queries from applications and users. - http://www.xyleme.com/