Customizing font kerning / letter spacing in Arial with FOP/XEP

After switching font from Verdana to Arial (company policy), we have gotten feedback that the 8pt text in tables is too tightly kerned and a bit hard to read. Increasing the font size is not an option due to space issues.

Is it possible to customize kerning beyond flipping the kerning attribute in the font config file to yes/no?

We have both FOP1.1 and XEP4.22 in the tool chain and need the customization for both.

Bergfrid