Scottish Gaelic has only 3 plural forms in QT linguist, but the language has 4

I tried to translate a string that's marked for plural into Scottish Gaelic (gd). The source file has the appropriate "gd" tag for the locale.

I am offered fields for Singular, Dual and Plural. However, Gaelic has 4 plural forms, not 3. The correct rule is:

nplurals=4; plural=(n==1 || n==11) ? 0 : (n==2 || n==12) ? 1 : (n > 2 && n < 20) ? 2 : 3;

I am working with QT Linguist 4.6.0, which seems to be the current version still.