Solution to Sub-pixel IE's bug with SASS

gistfile1.scss

// !!! NOT TESTED WITH WIDTH OR MARGIN NEGATIVE VALUES

// IE correction
@function correction($container-width){
  @return (0.5 / $container-width) * 100%;
}

//Fixed % to IE
@function pc($container-width: 0,$percentage: 0){
  @if $percentage == auto or $percentage == 0{
    @return $percentage;
  }@else{
    @return ( $percentage - correction($container-width) );    
  }
}

@mixin width($container-width: 0,$percentage: 0){
  .ie6 &,
  .ie7 &{
    width: pc($container-width,$percentage);
  }
    
  width: $percentage;
}

@mixin margin($container-width:0, $ptop: 0, $pright: 0, $pbottom: 0, $pleft: 0){
  
  margin: $ptop $pright $pbottom $pleft;
  
  .ie6 &,
  .ie7 &{
    margin: pc($container-width,$ptop) pc($container-width,$pright) pc($container-width,$pbottom) pc($container-width,$pleft);
  }

  
}

// EXAMPLE

#example{
  $width: 49;
  width: 49px;
  background-color: green;
  overflow: hidden;
  
  .title{
    background-color: red;
    width: #{$width}px;
    height: 50px;
  }
  
  .boxexample{
    @include width($width,25%);
    @include margin($width,20%,auto,0,0);
    height: 50px;
    float: left;
    background-color: blue;
  }
}