Nokia shares are plunging this morning after the Finnish phone maker confessed to investors that its current quarter and the full year are coming in weaker than expected. With quarter after quarter of decline, you have to ask whether NOK ( quote ) is the new Lucent at this point. Lucent -- now part of Alcatel Lucent ( ALU , quote ) -- deteriorated from above $80 a share to under $3 in the dot-com crash and recovered somewhat, but has yet to rise above $16 again: As it stands, NOK currently says the second quarter will be "substantially" below its previous guidance of 6.1 billion to 6.6 billion euros. And the shares are taking a beating: While the company promises "immediate" action to address its declining handset sales, the fact is that the company now seems trapped at the low end of the phone market, where profit margins are slim and only vast sales volumes can make a viable business. The value of NOK's alliance with Microsoft ( MSFT , quote ) to sell Windows smartphones remains to be seen, given less-than-enthusiastic pickup of the last generation of Windows phones. But now that NOK has effectively retired its proprietary smartphone platform Symbian, it is losing what share of that market it once had to hot competitors like AAPL ( quote ) and GOOG ( quote ).