Thanks Dan.
I ran this on R-2.15.1 with devel packages and get the same error. Any suggestions?
Here is the offending subset:
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library("GenomicRanges")
library("TxDb.Dmelanogaster.UCSC.dm3.ensGene")
exbygene <- exonsBy(TxDb.Dmelanogaster.UCSC.dm3.ensGene, "gene")
fl <- system.file("extdata", "untreated3_chr4.bam",
package="pasillaBamSubset")
reads <- readGappedAlignmentPairs(fl)
res <- summarizeOverlaps(exbygene, reads, "Union")
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