  Numerical simulations recover ultra slow electron holes (EH) of
electron-acoustic genre propagating stably well below the ion acoustic speed
where the ion response disallows any known pure electron perturbation. The
reason of stability of EH at high ion temperature ($T_{i}> T_{e}$) is traced to
the loss of neutralizing cold ion response. In a background of cold ions,
$\theta=T_e/T_i\gg 1$, they have an ion compression that accelerates to jump
over a forbidden velocity gap and settle on the high velocity tail of the
electron distribution $f_e$, confirming to a recently identified limit of the
nonlinear dispersion relation. For $\theta=T_e/T_i \le 1$, however, the warm
ions begin to supplement the electron response transforming the ion compression
to decompression at the hole location and triggering multiplicity of the scales
in trapped electron population which prompts an immediate generalization of the
basic EH theory.
