SDC warning 332174

Greetings,

I am getting the warning ID 332174 referring to my sdc file: Ignored filter at mobile_ddr_sdram.sdc(70): inst1|OffChipMemoryArbiterAndController_inst|mddr_ctrl_inst|ddr_pll_inst|altpll_component|auto_generated|pll1|clk[3] could not be matched with a clock.

However, looking in TimeQuest Timing Analyzer "Clocks" section, I do indeed see it list that path as a clock:

inst1|OffChipMemoryArbiterAndController_inst|mddr_ctrl_inst|ddr_pll_inst|altpll_component|auto_generated|pll1|clk[3]

In fact, I copied and pasted the exact string into my SDC file.

Any suggestions?