Problems with calculating years at leapdays

[MansMeg]

I'm having problems calculating years with leapyears.

library(lubridate)
dates <- ymd("2000-02-29", "2000-02-28")
intervals <- interval(start = dates, end = ymd("2014-09-25"))
try(intervals %/% years(1))
cat(geterrmessage())

## Error in while (any(start + est * per < end)) est[start + est * per <  : 
##   missing value where TRUE/FALSE needed

packageVersion("lubridate")

## [1] '1.3.3'

sessionInfo()

## R version 3.1.1 (2014-07-10)
## Platform: x86_64-apple-darwin13.1.0 (64-bit)
## 
## locale:
## [1] sv_SE.UTF-8/sv_SE.UTF-8/sv_SE.UTF-8/C/sv_SE.UTF-8/sv_SE.UTF-8
## 
## attached base packages:
## [1] stats     graphics  grDevices utils     datasets  methods   base     
## 
## other attached packages:
## [1] lubridate_1.3.3
## 
## loaded via a namespace (and not attached):
##  [1] digest_0.6.4     evaluate_0.5.5   formatR_0.10     htmltools_0.2.4 
##  [5] knitr_1.6        memoise_0.2.1    plyr_1.8.1       Rcpp_0.11.1     
##  [9] rmarkdown_0.2.64 stringr_0.6.2    tools_3.1.1      yaml_2.1.13

[vspinu]

Duplicate of #235