Easy.

Step 1: Understand the technical implication. There are myriads of books dedicated to fundamental trading software architectures, from the proprietary to universally accepted standards, readily available from your local library.

Step 2: Understand the finance function. Learn the role of a trading desk within a brokerage house and how it interacts with all the stakeholders - front office, middle office, back office (your support role), and externals - buy side firms for example. Be swift with the financial trading jargons, i.e. settlement of plain vanilla swaps

Step 3: Understand how technology (step 1) enables business (step 2). The criticality of financial systems, as you may know, is directly tied with monetary values. Any downtime during production has disastrous outcome. As you are an IT person beckoning with production support skills, you should fully understand SDLC, project specific methodologies and processes, and more importantly the criticality of the business impact (step 2) if the underlying code/configuration should fail (step 1).

Once you complete these steps - then you can go into vendor specific technologies: TIBCO, SeeBeyond, WebMethods, and standards: CORBA (old but sill out there), SOA, Cloud Computing (brand spankin' new) to get more in-depth understanding of their implementation and offerings.

-JB

Note: I am not an IT person (although I had a very short stint writing code once). I have run into tech gurus/honchos while developing strategy bus cases and conducting firm valuations, who just love to explain technical stuff with their never-ending squiggly lines on a whiteboard to non techs like me.