You can use your bardic music to influence creatures immune to mind-affecting effects.
Prerequisites: Cha 25, Perform 30 ranks, bardic music class feature.
Benefit: The character’s bardic music can affect even those normally immune to mind-affecting effects. However, such creatures gain a +10 bonus on their Will saves to resist such effects.
Source: Standard Reference Document under Open Game License v1.0a, which updated this feat originally published in the Epic Level Handbook, page 63.