Custom Logo dimensions for RT Theme


Just a cosmetic question about changing the Theme on RT 4.

I have a logo that is legible at 373X57 pixels. When I upload the custom logo is shown compressed into a 173X27 size. It is quite tiny and not legible and I wonder if there is a quick and easy way to fix this? I assume this restriction is to avoid throw off all the graphical elements on the page? Would appreciate it if there a way to tweak this.