Linux-based editors?

Hello Folks,

I have a very specific requirement of being able to create DocBook 
documents that will have text, tables, math equations, and images. So 
far, I have been looking at various XML editors, on Linux platform. 
However, I am unable to find any Linux-based editor that has DocBook 
support and equation editing capabilities. The closest workaround I have 
found is - use a commercial XML editor that has DocBook support and for 
equations use open-source equation editor such as Amaya  
(http://www.w3.org/Amaya/). Create MathML equations in Amaya, attach 
namespace & prefixes to the mathml. Insert these mathml equations in 
DocBook article in a <equation> elements, in XML edit mode. However, the 
intended Authors are not familiar with XML, so I would like to be able 
to operate in Author mode only, & not XML mode.

I was wondering if anyone has any solution for such a  specific requirement?

Appreciate your helpful replies.

TIA,
Anagha