How to use s.crossVisitParticipation from omniture?

Question

I cannot find documentations for this function anywhere, I am using version 1.7

s.crossVisitParticipation = new Function("v", "cn", "ex", "ct", "dl", "ev", "dv", ""
+ "var s=this,ce;if(typeof(dv)==='undefined')dv=0;if(s.events&&ev){var"
+ " ay=s.split(ev,',');var ea=s.split(s.events,',');for(var u=0;u<ay.l"
+ "ength;u++){for(var x=0;x<ea.length;x++){if(ay[u]==ea[x]){ce=1;}}}}i"
+ "f(!v||v==''){if(ce){s.c_w(cn,'');return'';}else return'';}v=escape("
+ "v);var arry=new Array(),a=new Array(),c=s.c_r(cn),g=0,h=new Array()"
+ ";if(c&&c!=''){arry=s.split(c,'],[');for(q=0;q<arry.length;q++){z=ar"
+ "ry[q];z=s.repl(z,'[','');z=s.repl(z,']','');z=s.repl(z,\"'\",'');arry"
+ "[q]=s.split(z,',')}}var e=new Date();e.setFullYear(e.getFullYear()+"
+ "5);if(dv==0&&arry.length>0&&arry[arry.length-1][0]==v)arry[arry.len"
+ "gth-1]=[v,new Date().getTime()];else arry[arry.length]=[v,new Date("
+ ").getTime()];var start=arry.length-ct<0?0:arry.length-ct;var td=new"
+ " Date();for(var x2=start;x2<arry.length;x2++){var diff=Math.round((td."
+ "getTime()-arry[x2][1])/86400000);if(diff<ex){h[g]=unescape(arry[x2][0"
+ "]);a[g]=[arry[x2][0],arry[x2][1]];g++;}}var data=s.join(a,{delim:',',"
+ "front:'[',back:']',wrap:\"'\"});s.c_w(cn,data,e);var r=s.join(h,{deli"
+ "m:dl});if(ce)s.c_w(cn,'');return r;");

here is my calling code.

s.eVar33 = s.crossVisitParticipation(s.campaign, 's_evar33', '30', '10', '>', 'purchase');

It keeps returning nothing, help would be appreciated. Thanks