As I understand it the Pre-standard PoE vs. the 802.3af standard is the available power. The pre-standard power supported up to 6.3 watts per port while the 802.3af standard supports up to 15.4 watts; more than double. So the short answer to this overview is yes.
There's actually more to it than that. The circuitry used to detect a pre-standard PoE device is different from IEEE, though I've long since forgotten the details. What this means though is that a switch needs to be specially designed to support both pre-standard PoE and IEEE PoE. As far as I know, all of the Catalyst series switches do support both forms, while the the majority of PoE switches from the different vendors do not. In the case of the ESW switches, it looks like you're in luck - I just doublechecked by plugging in an old 7960 to an ESW I have here and it powered up OK.
Introduction:Topology Diagram:Configuration Overview:Related
Information: Introduction: This document describes how to connect SG300
with Catalyst switch via STP. Spanning Tree Protocol (STP) is a Layer 2
protocol that runs on mainly on switches. The spec...
The Sx500 Series Stackable Switches offers different port features. You
can add security to a port, make the port more energy efficient, map a
VLAN to a port, make a port available or not to a specific network
portion, and so forth. The next set of articl...
Recently, HP Networking published a blog post attempting to counter the
favorable third party Miercom report on our Cisco® 200 and 300 Series
Smart and Managed switches: