Low-temperature muon spin-lattice relaxation measurements in the non-Fermi-liquid heavy-fermion alloys UCu_{5-x}Pd_x, x = 1.0 and 1.5, indicate inhomogeneously distributed f-electron spin fluctuation rates, and exhibit a time-field scaling of the muon relaxation function indicative of long-lived spin correlations. In UCu_4Pd the scaling exponent gamma is small and temperature independent. In UCu_{3.5}Pd_{1.5} gamma varies with temperature, increasing with decreasing temperature similar to spin-glass AgMn. This suggests that the spin-glass state found for x gtrsim 2 in UCu_{5-x}Pd_x modifies the low-frequency spin dynamics in UCu_{3.5}Pd_{1.5}.
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