Less: second call of parametric mixin keeps values from first call
===

I try to include web fonts with LESS. The parametric mixin which partly does the job is the following:

    .fontface(@fontName, @fontFile) { 
        @font-face { 
            font-family: @fontName;
            src: url("@{fontFile}.eot");    
            src: url("@{fontFile}.eot?#iefix") format('embedded-opentype'),
            url("@{fontFile}.woff") format('woff'),
            url("@{fontFile}.ttf") format('truetype'),
            url("@{fontFile}.svg#DistantGalaxyRegular") format('svg');
            font-weight: normal;
            font-style: normal; } }
    .font(@fontsize:10pt, @fontName:"Aierbazzi", @fontFile:"Aierbazzi-fontfacekit/aierbazzi-webfont") { 
            .fontface(@fontName, @fontFile);
    font-family:@fontName;
    font-size:@fontsize; }
It works fine being called the first time:

    .font1 { .font(24pt, "Black-Rose","Black-Rose-fontfacekit/BLACKR-webfont"); }
    .font4 { .font(24pt, "bubblegum-sans","bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont"); }

results in:

    .font1 { 
        font-family:"Black-Rose";
        font-size:24pt; }
        @font-face { 
            font-family:"Black-Rose";
            src:url("Black-Rose-fontfacekit/BLACKR-webfont.eot");
            src:url("Black-Rose-fontfacekit/BLACKR-webfont.eot?#iefix") format('embedded-opentype'),url("Black-Rose-fontfacekit/BLACKR-webfont.woff") format('woff'),url("Black-Rose-fontfacekit/BLACKR-webfont.ttf") format('truetype'),url("Black-Rose-fontfacekit/BLACKR-webfont.svg#DistantGalaxyRegular") format('svg');
            font-weight:normal;
            font-style:normal; }

    .font4 { 
        font-family:"bubblegum-sans";
        font-size:24pt; }
        @font-face { 
            font-family:"Black-Rose";
            src:url("Black-Rose-fontfacekit/BLACKR-webfont.eot");
            src:url("Black-Rose-fontfacekit/BLACKR-webfont.eot?#iefix") format('embedded-opentype'),url("Black-Rose-fontfacekit/BLACKR-webfont.woff") format('woff'),url("Black-Rose-fontfacekit/BLACKR-webfont.ttf") format('truetype'),url("Black-Rose-fontfacekit/BLACKR-webfont.svg#DistantGalaxyRegular") format('svg');
            font-weight:normal;
            font-style:normal; }

when I swap the 2 lines around:

    .font4 { .font(24pt, "bubblegum-sans","bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont"); }
    .font1 { .font(24pt, "Black-Rose","Black-Rose-fontfacekit/BLACKR-webfont"); }

again just the first web font is registered in the CSS:

    .font4 { 
        font-family:"bubblegum-sans";
        font-size:24pt; } 
    @font-face { 
        font-family:"bubblegum-sans";
        src:url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.eot");
        src:url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.eot?#iefix") format('embedded-opentype'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.woff") format('woff'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.ttf") format('truetype'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.svg#DistantGalaxyRegular") format('svg');
        font-weight:normal;
        font-style:normal;}

    .font1 { 
        font-family:"Black-Rose";
        font-size:24pt; }
    @font-face { 
        font-family:"bubblegum-sans";
        src:url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.eot");
        src:url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.eot?#iefix") format('embedded-opentype'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.woff") format('woff'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.ttf") format('truetype'),url("bubblegum-sans-fontfacekit/BubblegumSans-Regular-webfont.svg#DistantGalaxyRegular") format('svg');
        font-weight:normal;
        font-style:normal; }

What could be the reason? I am clueless in the moment.
Thank you very much in advance.