actually getting icon stacks to work in ie7

build/assets/font-awesome/css/font-awesome.css

@@ -245,7 +245,6 @@ ul.icons-ul > li .icon-li {
 .icon-stack {
   position: relative;
   display: inline-block;
-  text-align: center;
   width: 2em;
   height: 2em;
   line-height: 2em;
@@ -254,14 +253,17 @@ ul.icons-ul > li .icon-li {
 .icon-stack [class^="icon-"],
 .icon-stack [class*=" icon-"] {
   display: block;
+  text-align: center;
   position: absolute;
   width: 100%;
   height: 100%;
   font-size: 1em;
   line-height: inherit;
+  *line-height: 2em;
 }
 .icon-stack .icon-stack-base {
   font-size: 2em;
+  *line-height: 1em;
 }
 /* Animated rotating icon */
 .icon-spin {

build/assets/font-awesome/less/mixins.less

@@ -11,7 +11,6 @@
   .icon-stack {
     position: relative;
     display: inline-block;
-    text-align: center;
     width: @width;
     height: @height;
     line-height: @width;
@@ -19,14 +18,17 @@
     [class^="icon-"],
     [class*=" icon-"] {
       display: block;
+      text-align: center;
       position: absolute;
       width: 100%;
       height: 100%;
       font-size: @top-font-size;
       line-height: inherit;
+      *line-height: @height;
     }
     .icon-stack-base {
       font-size: @base-font-size;
+      *line-height: @height / @base-font-size;
     }
   }
 }