  We observed the 2006 superoutburst of SDSS J080434.20+510349.2 during its
plateau phase, rebrightening phase, and post-superoutburst final decline. We
found that this object is a grazing eclipsing system with a period of
0.0590048(2) d. Well-defined eclipses were only observed during the late stage
of the superoutburst plateau and the depth decreased during the subsequent
stages. We determined the superhump period during the superoutburst plateau to
be 0.059539(11) d, giving a fractional superhump excess of 0.90(2)%. During the
rebrightening and post-superoutburst phases, persisting superhumps with periods
longer than those of superhumps during the plateau phase: 0.059632(6) during
the rebrightening phase and 0.05969(4) d during the final fading. This
phenomenon is very well in line with the previously known long-period "late
superhumps" in GW Lib, V455 And and WZ Sge. The amplitudes of orbital humps
between different states of rebrightenings suggest that these humps do not
arise from the classical hot spot, but are more likely a result of projection
effect in a high-inclination system. There was no clear evidence for the
enhanced hot spot during the rebrightening phase. We also studied previously
reported "mini-outbursts" in the quiescent state and found evidence that
superhumps were transiently excited during these mini-outbursts. The presence
of grazing eclipses and distinct multiple rebrightenings in SDSS
J080434.20+510349.2 would provide a unique opportunity to understanding the
mechanism of rebrightenings in WZ Sge-type dwarf novae.
