Joining Array Elements Based On Last Character

I have an array of strings. Some of the strings have a continuation character at the end (in this case '='). What I need to do is append the element that contains that character (eliminating it) with the next element and reduce the size of the array by 1. My problem is arising (I used variations of split/join) when that character occurs someplace other than the end of the string. How can I check the last character in a string element and join it with the next string element? TIA. I can do it using brute force but am looking for something more elegant if possible.

Code:
for ($i=0; $i<$lines.length; $i++) {
if ($lines[$i].substr($lines[$i].length-1)=="=") {
$lines[$i]=$lines[$i].substr(0,$lines[$i].length1)+$lines[$i+1];
$lines.splice($i+1,1);
$i--;
}
}