The technology is old alas the surrounding tools must be just as old.

This is actually true.

We have heaps of tools that requires access via 3270 terminal software to the mainframe.

In addition, we also have a range of Windows based tools. 
As many of you know, the financial industry is sleeping tight with IBM when it comes to technology and tools. On the development tools this means that we are using Eclipse based tools both for modelling (UML) and developing (Cobol, PL/1, Java, etc).