Using:
table { border-spacing: 0; }
Example:
table{-fs-table-paginate:paginate;} td{border:1px solid red}

table{-fs-table-paginate:paginate;border-spacing:0} td{border:1px solid red}

The result is not quite the same (that the TD boundaries do not merge), but it can be fixed by setting the boundaries on only one side of the TD.
#t4{-fs-table-paginate:paginate;border-spacing:0} #t4 td{border-width:0 1px 1px 0;border-color:red} #t4 tr.firstrow td{border-top-width:1px} #t4 td.firstcol{border-left-width:1px}

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