Two errors on php 5.3.3 (so far):

A PHP Error was encountered

Severity: 8192

Message: Assigning the return value of new by reference is deprecated

Filename: src/EsuRestApi.php

Line Number: 1354

A PHP Error was encountered

Severity: 8192

Message: Call-time pass-by-reference has been deprecated

Filename: src/EsuRestApi.php

Line Number: 1895

The first error refers to this line:

$req = &new HTTP_Request2( $url, $args );

resolution: remove the ampersand.

The second one refers to this line:

$this->parseReplicas( $dom->getElementsByTagName( "replica"), &$info->replicas );

resolution:  removed the ampersand.

EDIT - More errors:

Message:  Function split() is deprecated

Filename: src/EsuRestApi.php

Line Number: Somewhere near 1832 (I've been commenting out the deprecated lines & trying to fix, so line number is off by a few lines).

resolution: use explode() instead.