After wasting a day on buggy jquery -input-mentions i found this working perfectly. Modified it for multi-trigger for my need. Here is quick hack with least possible change in existing code as others are also interested in it.
Add one more option at line 20
triggerArray: new Array('@','#'),
Add these in search function after assignment of variable at line 144 above
var triggerIndex = $.map(this.options.triggerArray,function(val,i){
return contents.lastIndexOf(val);
});
this.options.trigger = this.options.triggerArray[triggerIndex.indexOf(Math.max.apply(window,triggerIndex))];
Now request will be initiated at each element in triggerArray.