Issue: The IRC doesn't appear to work (through browser)

[Legobricks]

Details I was provided of the error, which was named ClassNotFoundException:

Java Plug-in 10.7.2.11
Using JRE version 1.7.0_07-b11 Java HotSpot(TM) Client VM
User home directory = C:\Documents and Settings\x
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c:   clear console window
f:   finalize objects on finalization queue
g:   garbage collect
h:   display this help message
l:   dump classloader list
m:   print memory usage
o:   trigger logging
q:   hide console
r:   reload policy configuration
s:   dump system and deployment properties
t:   dump thread list
v:   dump thread stack
x:   clear classloader cache
0-5: set trace level to <n>
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