Created Unassigned: Semicolons in LESS mixin parameters [39]

I'm using BundleTransfomer.Core 1.7.19 and BundleTransformer.Less 1.7.16 with the new Twitter Bootstrap (3.0.0 RC1) and when rendering the page I get:

```
BundleTransformer.Core.Translators.AssetTranslationException: During translation of LESS-code, readed from the file /Content/less/main.less, to CSS-code syntax error has occurred.
See more details:

Expected ')' but found ' ' on line 70 in file '/Content/less/dropdowns.less':
[69]: color: @dropdown-link-hover-color;
[70]: #gradient > .vertical(@start-color: @dropdown-link-hover-bg; @end-color: darken(@dropdown-link-hover-bg, 5%));
---------------------------------------------------------------^
[71]: }
```
It seems to be annoyed with the semicolons in mixin parameters, but as far as I'm aware, this is valid LESS.