Sometimes, when I right-click in a private conversation window and I CTCP PING that person, for example (but this affects the other options too), mIRC will ping another nick (like the window would be "transparent" and it will choose something that's "under" it). This appears in all mIRC versions up to 6.03; I haven't tested it for 6.1.

I just did a quick test, it appears to work in mirc 6.1

It works? What do you mean? Anyway, I tested it in mIRC 6.1 the the bug is still there...

This bug has been reported for many versions, unfortunately I have never been able to reproduce it.

Are you able to reproduce it with a clean install of mIRC, with no scripts, etc.? If not, perhaps you have a popup or script loaded that is causing his to happen.

If you find a way to reproduce it with a clean install of mIRC with specific changes, that would help a lot.

Well, I have a standard version of mIRC... almost standard - I configured it a little bit. I include it here, omitting irrelevant lines:

[text]
linesep=none
quit=(none)
timestamp=[HH:nn]
accept=*.bmp,*.gif,*.jpg,*.log,*.mid,*.mp3,*.ogg,*.png,*.txt,*.wav,*.wma,*.zip
theme=mIRC Classic
[options]
n0=1,1,0,1,0,1,300,1,1,1,0,0,0,0,0,0,1,0,1,0,4096,0,1,0,1,1,1,1,0,50,1,1,0,1,0
n1=5,100,0,1,0,0,0,0,1,1,1,1,1,1,1,1,0,1,0,0,1,1,0,0,5,0,1,0,0,0,0,0,0,0,0,10
n2=0,0,0,1,1,1,1,1,0,60,120,1,1,1,0,0,1,1,0,120,20,10,0,1,1,1,1,1,0,0,1,1,0,0,1
n3=5000,0,0,0,1,0,0,1,0,1,1,1,0,1,1,1,1,1,0,1,0,0,1,0,1,1,0,1,0,0,0,3,180,0,0
n4=1,0,1,1,0,3,9999,0,0,0,1,0,1024,0,1,9999,120,0,1,0,2,1,1,1,1,5000,1,5,0,0,3,0,1,1,0
n5=1,1,1,1,1,1,1,1,1,1,6667,500000,1,2,1,1,1,1,300,30,10,0,1,26,0,1,1,8192,1,0,0,82,1,1
n6=0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,0,100,1,1,0,0,0,1,0,4,0,0,1
n7=0,0,0,0,0,1,0,1,1,1,1,1,0,1,1,0,1,70,0,3,0,0,1,1,1,1,1,0,0,0,1,0,0,1,1
[language]
sjis=0
multibyte=1
[clicks]
status=/lusers
query=/whois $$1
channel=/channel
nicklist=/query $$1
notify=/whois $$1
message=/whois $$1
[marker]
show=off
size=3
colour=4
method=1
[styles]
thin=3
font=1
hide=1
color=default
size=2
buttons=0
[windows]
main=185,600,27,490,2,1,0
wchannel=84,596,84,376,0,1,0
wquery=56,596,56,376,2,1,0
wchat=196,596,196,376,2,1,0
wdccs=-1,269,-1,268,0,1,0
wdccg=-1,269,-1,268,0,1,0
wfinger=-1,596,-1,376,0,1,0
scripts=25,473,45,441,0,0,0
status=0,823,0,551,2,1,0
[background]
status=none
[colours]
n0=0,6,4,5,2,3,3,3,3,3,3,1,5,7,6,1,3,2,3,5,1,0,1,0,1,15,6,0
[colors]
n0=mIRC Classic,0,6,4,5,2,3,3,3,3,3,3,1,5,7,6,1,3,2,3,5,1,0,1,0,1,15,6,0
[palettes]
n0=16777215,0,8323072,37632,255,127,10223772,32764,65535,64512,9671424,16776960,16515072,16711935,8355711,13816530

There isn't always possible to reproduce it, but I realized that if it happened one, there are more changes it will hapen again in the close future. And I think that it happens less often in mIRC 6.1 (I'm not sure, however).

I also add an excrept from one of my logs. Please ignore the language (Romanian), but observe the effect I was talking about:

<GrayShade> gata.........
<GrayShade> bine... am mai luat articole de pe net intr timp
<TheCreeep> offff
<TheCreeep>
<TheCreeep> ok, merci
-> [gata........] PING
-> [TheCreeep] PING
<GrayShade> te-ai uitat prin ele?
<TheCreeep> putin

P. S.: I thought my English was better...