[Qgis-developer] qgis: symbol lookup error

[nitin quick]

greetings,
i have got some strange error.
Scenario is: in my plugin i want to have a popup dialog come up . So
put a new button in tool bar and connected its signal witha slot
responsible for generating or setting this dialog-ui.
But this resulted in similar error
qgis: symbol lookup error. unable to find symbol
:-Z123finddialog23QWidget32( not completely accurate but wit same
wordings).
What sense it make to me is library is not built corresponding class.
So i made an entry in makefile.am in  my plugin directory at line
libqgis_plugin_oprtool_la_sources:..
here oprtool is name of plugin.
But when i compiled program from here, Plugin menu donot lists my
plugin. So i can't activate it.
I have no idea what made it happened??

regards
quickNitin